1. Field of the Invention:
The invention relates in general to electrical transformers, and more specifically to rotating flux transformers.
2. Description of the Prior Art:
Co-pending application Ser. No. 607,852, filed May 7, 1984 entitled "Low Core Loss Rotating Flux Transformer", which is assigned to the same assignee as the present application, discloses a transformer construction in which a rotating induction vector is achieved throughout all of the magnetic core material. By adjusting the excitation current to saturate the magnetic core, i.e., provide a saturated rotating induction vector, the hysteresis core loss is eliminated. Also, since magnetic domains disappear at saturation, eddy current losses influenced by magnetic domain size are reduced. This is an especially significant reduction in losses for amorphous alloys, because of their large domains.
To obtain a rotating induction vector, two magnetic fluxes approximately 90.degree. out of phase must be generated in the magnetic core. The co-pending application discloses obtaining the desired 90.degree. phase shift from a single-phase source via reactive elements; or, from a three-phase source by vectorially combining two phases of proper polarity to obtain a voltage 90.degree. at a phase with the remaining phase voltage. Thus, in a single-phase embodiment, considerable cost would be involved in the reactive components associated with the phase shift function. In a three-phase embodiment three different vector combinations each involving a different pair of phases would be required.
Co-pending application Ser. No. 607,852 is hereby incorporated into the specification of the present application by reference.